1. Field of the Invention
The present invention is in the field of vapor deposition apparatus, employing a plate type susceptor for supporting a wafer on which a film is to be grown. A radio frequency heating unit applies heat to the wafer while the wafer is supported on the susceptor. The temperature of the wafer is sufficient to cause a chemical reaction to occur in the reaction gas which is fed into the chamber, causing the formation of a film on the surface of the wafer.
2. Description of the Prior Art
Conventional vapor deposition methods and apparatus are classified essentially into the vertical type and the barrel type vapor deposition systems.
In the vertical type vapor deposition apparatus, a susceptor is horizontally disposed in a bell jar, a radio frequency induction coil is arranged below the susceptor, and a reaction gas supply nozzle extends through the centers of the susceptor and the coil. With this arrangement, the susceptor is rotated with respect to the nozzle during the vapor deposition.
In a barrel type vapor deposition apparatus, a susceptor in the form of a hexagonal cone is disposed in a bell jar and a lamp for heating the susceptor by radiation heat is disposed outside the bell jar. A reaction gas supply port is arranged at an upper portion of the bell jar. With this type of arrangement, the susceptor is rotated with respect to the bell jar during the vapor deposition process.
With increased diameter wafers used in the conventional vertical type vapor deposition apparatus, the diameters of the susceptor and the bell jar are necessarily increased, thus increasing the installation area of the apparatus.
Also, in the conventional barrel type vapor deposition apparatus, the apparatus as a whole becomes bulky when the wafer size is increased. As a result, maintenance becomes cumbersome, and the evacuation time is prolonged, thus prolonging the production cycle. Radiation heating by the lamp also has a low power efficiency as compared with radio frequency induction heating. Furthermore, since the susceptor comprises a hexagonal cone, it is difficult to improve productivity by automating the wafer loading.